I've never understood Lacuna Coil either. Every time I try to go back and listen to them (as it's not uncommon for me to continually re-evaluate a band every couple of years) I don't get why they're so popular in the metal world. Nightwish still rocks, although I'm disappointed that Tarja's been cutting back on the operatic vocals in favor of standard singing.
Hell, truth be told, with the exception of Nightwish and Gathering's first two with Anneke, I don't listen to much female fronted metal, though I love gothic metal (Paradise Lost, My Dying Bride and Candlemass are among my favorite bands) but mostly male-fronted bands.
(well, there's also Doro Pesch, but most metalheads seem to forget about her)